I have a '99 1500 5.2. Two questions about headers and cat-back exhausts (as it would relate to a single out setup, not duals):

1) From the cat forward is a y-shaped pipe that connects the catalytic converter with the exhaust manifolds. I beleive it is simply called a y-pipe. So, if I want to install Mopar performance headers (not shorties), do you also have to get a new shorter y-pipe to connect your headers to your cat? Just looking at the length of my current y-pipe, and the length of most non-shorty headers, I see no way they would line up together.

2) If I decide to install a cat-back performance exhaust first, and do headers later, my cat-back should not be impacted by putting in long headers later, right? I just don't want to spend the money on a nice performance cat-back, only to find out I would need a different one later because it won't line up with headers.

Thanks.

 

1)yes you have to get a different y-pipe for long tube headers...you can buy them online at a number of places.
2) cat back will not be affected because its from the cat back. your catalytic converter acts like a connector between the 2 linking one to the other.

you can do all types of combinations...longtube headers, y-pipe, no cat, muffler....i believe there's a possible 48 different combinations of exhaust set ups... take your pick

 

Remember, removing the cat is a federal offense that carries a $2500 fine. Any cop can write you if they want to be a bastid. That being said, my Blazer hasn't had a cat since 1997. But it's an offroad only vehicle now.

I'm planning a system for my Ram that involves shorty headers and true duals, with dual cats. Just hope the current system lasts til it's warm out...

 

So could you get the longtube headers, custom y-pipe, hi flow cat w/ dual cat back exhaust? Will these lonmgtube headers affect the o2 sensors at all?

 

Your o2 sensors are on either side of the cat, so the headers don't affect them at all. Any true dual system will have to be custom bent by a good exhaust shop, which makes it a bit more pricey, as does adding a second cat. I'm not sure how the o2 sensors will react to a true dual system. Dodge had a heavy duty emissions package on the 3/4 and 1 tons that came from the factory with true duals and dual cats. I may just find an aftermarket replacement for that system. It has a single o2 sensor before each cat, and requires a different PCM, possibly different wiring but I'm not sure.

 

On my truck there is only one 02 before the cat too. So would I have to change my PCM or wiring on mine.